Near Infrared Spectroscopy (NIRS) is a non-invasive, FDA approved, bedside technology that allows determination of regional oxygen saturations (rSO2) in tissues such as the gut mesentery. Using NIRS, the oxygenation status of hemoglobin in tissues located 2-4 cm below the skin can be determined and recorded continuously (12). For instance, Dave et al. used NIRS to demonstrate that splanchnic rSO2, but not cerebral rSO2, increases after feeds in the stable prematurely born infant tolerating full bolus orogastric feedings (13). Of importance, the average hematocrit in this study group was 37% (±7) and therefore these babies had no significant anemia.